The present disclosure relates to electronic devices and, more particularly, to user interfaces for electronic devices.
Electronic devices can control users' access to many different types of secure programs responsive to security numbers that are entered by the users. Example electronic devices can include mobile phones, tablet computers, laptop computers, etc. Example secure programs can include any program which requires the user to correctly enter a personal identification number or other security number to obtain access to a protected operation, such as to unlock a user interface, login to a user account, and/or access confidential information. Maintaining confidentiality of the security number is therefore important. However, the proliferation of mobile electronic devices has increased the likelihood that a user will enter a security number in a public setting where the security number may become compromised by another person. The other person may directly observe numeric digits that the user touch-types on a display of the device or may infer the user's selections based on observing movement of the user's finger relative to a known keypad layout.